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An Asynchronous 32×8-Bit Multiplier Based on LDCVSPG Logic
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作者 ZHONG Xiongguang RONG Mengtian 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期294-298,共5页
An asynchronous high-speed pipelined 32×8-bit array multiplier based on latched differential cascode voltage switch with pass-gate (LDCVSPG) logic is presented. The multiplier is based on 4-phase dual-rail prot... An asynchronous high-speed pipelined 32×8-bit array multiplier based on latched differential cascode voltage switch with pass-gate (LDCVSPG) logic is presented. The multiplier is based on 4-phase dual-rail protocol. HSPICE analysis using device parameters of Central Semiconductor Manufacturing Corporation (CSMC's) 0.6μm CMOS technology is also given, and the result shows that the average data throughput of the multiplier is 375 MHz. 展开更多
关键词 asynchronous circuit LDCVSPG array multiplier 4-phase dual-rail protocol
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Characterization of a 3-Phase a.c. Free Burning Arc Plasma 被引量:1
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作者 夏维东 Laurent FULCHERI +2 位作者 Jose GONZALEZ-AGUILAR 李辉 Thomas M. GRUENBERGER 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第2期156-163,共8页
A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed ... A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed neutral point. This gives rise to a rich and complex phenomenology related to instabilities and arc motion since the arcs are "burning" freely in the gas flow between the three electrodes. This paper is dedicated to the analysis of the behavior of such a system under typical conditions using argon and nitrogen as plasma gases. A classification of are configuration, arc commutating, arc interaction, arc motion and arc instabilities are discussed based on ultra high-speed cine camera analysis. A simple model describing the time evolution of the system is also presented and compared with the experimental measurements. The results show that an adequate control could allow the improvement of the overall system. 展开更多
关键词 3-phase AC arc plasma free arc arc motion arc commutating arc instabilities
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A new design of stator magnetic system for 3-phase & 12-pole HB stepper
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作者 任雷 史敬灼 王宗培 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期52-56,共5页
A new design of stato magnetic System is Proposed for 3-phase & 12-pole HB stepper, and it features bet-ter distribution of magntic lield to incare Pullou tope and bopmve Operaonal stability of moor and minimummut... A new design of stato magnetic System is Proposed for 3-phase & 12-pole HB stepper, and it features bet-ter distribution of magntic lield to incare Pullou tope and bopmve Operaonal stability of moor and minimummutual inductance between phase windimp to make design of control circuit easier, and application proved it is as good as expected. 展开更多
关键词 HB STEPPER STATOR MAGNETIC system 3-phase STEPPER
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Improvement of β-phase crystal formation in a BaTiO3-modified PVDF membrane
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作者 Lin SHEN Lei GONG +3 位作者 Shuhua CHEN Shiping ZHAN Cheng ZHANG Tao SHAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第6期144-151,共8页
In this paper,low temperature plasma is used to modify the surface of barium titanate(BaTiO3)nanoparticles in order to enhance the interfacial compatibility between ferroelectric poly(vinylidene fluoride)(PVDF) ... In this paper,low temperature plasma is used to modify the surface of barium titanate(BaTiO3)nanoparticles in order to enhance the interfacial compatibility between ferroelectric poly(vinylidene fluoride)(PVDF) and BaTiO3 nanoparticles.The results demonstrate that oxygenic groups are successfully attached to the BaTiO3 surface,and the quantity of the functional groups increases with the treatment voltage.Furthermore,the effect of modified BaTiO3 nanoparticles on the morphology and crystal structure of the PVDF/BaTiO3 membrane is investigated.The results reveal that the dispersion of BaTiO3 nanoparticles in the PVDF matrix was greatly improved due to the modification of the BaTiO3 nanoparticles by air plasma.It is worth noting that the formation of a β-phase in a PVDF/modified BaTiO3 membrane is observably promoted,which results from the strong interaction between PVDF chains and oxygenic groups fixed on the BaTiO3 surface and the better dispersion of BaTiO3 nanoparticles in the PVDF matrix.Besides,the PVDF/modified BaTiO3 membrane at the treatment voltage of 24 k V exhibits a lower water contact angle(≈68.4°) compared with the unmodified one(≈86.7°).Meanwhile,the dielectric constant of PVDF/BaTiO3 nanocomposites increases with the increase of working voltage. 展开更多
关键词 PVDF BaTiO3 NANOCOMPOSITE non-thermal plasma β-phase ferroelectric
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3-Phase Modeling for the Origin of Chinese Lithium-Rich Brines
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作者 HUANG Wenbin WU Xishun +1 位作者 DU Xiaohui LI Li 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期339-340,共2页
There are significantly different origins and mineralizations among various lithium-rich brines of the world.As for Clayton Valley,Nevada,the data and interpretations recently presented suggest that the model
关键词 3-phase modeling lithium brine origin Qaidam Basin
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Fault diagnosis algorithm for 3-phase passive rectifiers based on frequency-domain analysis for acceleration grid power supply in CFETR NBI system
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作者 Bangyou ZHU Shaoxiang MA +3 位作者 Hongqi ZHANG Zhiheng LI Ming ZHANG Yuan PAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第12期40-54,共15页
The acceleration grid power supply(AGPS) is a crucial part of the Negative-ion Neutral Beam Injection system in the China Fusion Engineering Test Reactor,which includes a 3-phase passive(diode) rectifier.To diagnose a... The acceleration grid power supply(AGPS) is a crucial part of the Negative-ion Neutral Beam Injection system in the China Fusion Engineering Test Reactor,which includes a 3-phase passive(diode) rectifier.To diagnose and localize faults in the rectifier,this paper proposes a frequencydomain analysis-based fault diagnosis algorithm for the rectifier in AGPS.First,time-domain expressions and spectral characteristics of the output voltage of the TPTL-NPC inverter-based power supply are analyzed.Then,frequency-domain analysis-based fault diagnosis and frequency-domain analysis-based sub-fault diagnosis algorithms are proposed to diagnose open circuit(OC) faults of diode(s),which benefit from the analysis of harmonics magnitude and phase-angle of the output voltage.Only a fundamental period is needed to diagnose and localize exact faults,and a strong Variable-duration Fault Detection Method is proposed to identify acceptable ripple from OC faults.Detailed simulations and experimental results demonstrate the effectiveness,quickness,and robustness of the proposed algorithms,and the diagnosis algorithms proposed in this article provide a significant method for the fault diagnosis of other rectifiers and converters. 展开更多
关键词 fault diagnosis 3-phase passive rectifier acceleration grid power supply(AGPS) fault localization
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A Device for Measuring 3-Phase Alternating Current at a Distance
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作者 Seppo Makinen 《Journal of Electromagnetic Analysis and Applications》 2015年第8期209-216,共8页
We have made a preliminary study on a possibility to build a device, which could measure three-phase alternating current at a distance. This report gives a brief look at the theoretical background related with such a ... We have made a preliminary study on a possibility to build a device, which could measure three-phase alternating current at a distance. This report gives a brief look at the theoretical background related with such a device and derives several mathematical results associated with the theory and the structure of the device. Our results suggest that such a device can be built, assuming the distances between the three current-carrying wires and the two sensors of the device are known accurately enough. There are ways to measure these distances, but this article does not concentrate on them. 展开更多
关键词 Electromagnetic Induction 3-phase Alternating Current AMMETER
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12/3相双绕组异步发电机自激起励时谐波谐振问题研究 被引量:22
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作者 顾伟峰 马伟明 +2 位作者 王东 肖飞 张波涛 《中国电机工程学报》 EI CSCD 北大核心 2004年第6期167-171,共5页
12/3相双绕组异步发电机是将交直流双绕组发电理论应用到异步发电中、作为独立电源而提出的。这种电机在定子上布置了两套绕组,即一套4Y移15°十二相整流绕组和一套三相静止励磁绕组(或称补偿绕组)。其中整流绕组经整流桥向直流负... 12/3相双绕组异步发电机是将交直流双绕组发电理论应用到异步发电中、作为独立电源而提出的。这种电机在定子上布置了两套绕组,即一套4Y移15°十二相整流绕组和一套三相静止励磁绕组(或称补偿绕组)。其中整流绕组经整流桥向直流负载供电,而励磁绕组提供无功功率,以保持负载时整流绕组端电压不变。当发电机十二相绕组并接起励电容后起动时发生了高次谐波谐振,导致无法建立基波电压。该文分析了发生谐振后的电机内气隙磁场的特点,查明了发生谐波谐振的原因,提出了研究双绕组异步发电机自激起励时谐波谐振问题的数学模型,并得出了发生谐振后的稳态等值电路,最后得到谐振频率的计算公式。计算结果与试验数据的比较表明该文提出的数学模型是正确的。 展开更多
关键词 12/3相双绕组异步发电机 自激起励 谐波 谐振 励磁绕组 数学模型
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Hyperbranched phthalocyanine enabling black-phase formamidinium perovskite solar cells processing and operating in humidity open air 被引量:1
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作者 Rong Li Jiale Ding +6 位作者 Xijiao Mu Yifei Kang Anran Wang Weihui Bi Yunhe Zhang Jing Cao Qingfeng Dong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第8期141-149,I0005,共10页
The extreme instability of pureα-phase FAPbI_(3) under high humidity conditions restricts the highthroughput fabrication in unmodified air environments,resulting in poor performance ofα-phase FAPbI_(3) perovskite de... The extreme instability of pureα-phase FAPbI_(3) under high humidity conditions restricts the highthroughput fabrication in unmodified air environments,resulting in poor performance ofα-phase FAPbI_(3) perovskite devices obtained by scalable fabrication methods.Here we synthesized hyperbranched copper phthalocyanine(HCuPc)as a supramolecular additive with twisted phthalocyanine units to realize the molecular-level encapsulation at the grain boundaries through supramolecular interaction,which greatly broadened the processing window of FAPbI_(3) under high humidity.At the same time,unlike traditional encapsulation layer that carrier can only be collected by tunneling effect,the twisted phthalocyanine ring of HCu Pc in perovskite films is more conducive to hole extraction.Finally,a record efficiency was achieved in pure FAPbI_(3) based inverted structured solar cell by blade-coating to the best of our knowledge,even under unmodified humid air conditions(relative humidity of 65%–85%).The best operational stability of 3D pure FAPbI_(3) devices can also be achieved at the same time and unencapsulated HCuPc-FAPbI_(3) device can even operate with negligible degradation for 100 h in the open air(RH 30%–40%). 展开更多
关键词 Perovskite solar cells α-phase FAPbI_(3) Blade coating Humid air stability Copper phthalocyanine
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ON THE ORDERING TRANSFORMATIONS IN Ti_3AL-Nb ALLOY
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作者 LI Dong ZHOU Jing CHANG Xin GUAN Shaoxuan Institute of Metal Research,Academia Sinica,Shenyang,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1991年第3期204-208,共5页
Study was made of the behaviour of ordering transformation in Ti_3AI-Nb alloy,including the ordering at high temperatures,the transformation of high temperature β-phase during cooling,and the decomposition of metasta... Study was made of the behaviour of ordering transformation in Ti_3AI-Nb alloy,including the ordering at high temperatures,the transformation of high temperature β-phase during cooling,and the decomposition of metastable β-phase during aging.The results show that the ordered primary α_2 and high temperature β in alloy form at 1060℃.The transformation of high temperature β-phase proceed by β→α_2+ω type during cooling,and the decomposition of metastable β and ω type proceeded by(β+ω)_(metustabte)→(α_2+β)_(stable)during aging at 700℃. 展开更多
关键词 Ti_3Al-Nb alloy ordering transformation α_2-phase β-phase ω-phase
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Three Applications of V.3 Google Maps: Just for Display of Data, or Analysis as Well?
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作者 Alan G. Phipps 《Journal of Geographic Information System》 2014年第5期548-558,共11页
A question about the analytical capability of Google maps is answered for three examples of pin maps, and polyline and polygon maps that are computer-programmed with the third version of the Google maps application. O... A question about the analytical capability of Google maps is answered for three examples of pin maps, and polyline and polygon maps that are computer-programmed with the third version of the Google maps application. One map reads XML data stored on the home server, whereas another downloads its data from an online fusion table, and the third includes pre-programmed data. Each map permits users to query mashup layers after the map has loaded. However, an analytical capability comparable to GIS should require users to have access to their data for analysis with their own functions while the map is loading. The technical constraint of asynchronous loading of data for Google maps is illustrated for each map. In conclusion, only one map has an analytical capability that is achieved by means of deprecated synchronous loading of data. 展开更多
关键词 V.3 Google MAPS Pin MAPS POLYGON MAPS XML DATA Fusion Table asynchronous Loading
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基于确定性网络的网端一体流量交换机制
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作者 王晨阳 张亚生 《计算机测量与控制》 2023年第1期270-275,共6页
低轨卫星通信系统不受地理条件限制,相比于地面通信有覆盖范围广、运维成本低、部署周期短等优点,因此逐渐受到人们的关注;但对于低轨星座来说,拥有众多卫星节点的无线多跳网络,总传输和处理时延明显增大;确定性网络是近几年工业界新提... 低轨卫星通信系统不受地理条件限制,相比于地面通信有覆盖范围广、运维成本低、部署周期短等优点,因此逐渐受到人们的关注;但对于低轨星座来说,拥有众多卫星节点的无线多跳网络,总传输和处理时延明显增大;确定性网络是近几年工业界新提出的一种网络技术,可以解决传统传统网络有关丢包和时延相关的需求,这与低轨卫星网络的需求相同;研究了地面网络确定性网络的关键技术和卫星网络的相关特征,将确定性网络技术应用到低轨星座,将ATS异步流量整形算法应用到星地间流量控制上,提出一种星载交换机制,优化了星载交换机的资源使用和丢包;借助NS3软件仿真了相关场景,并对结果进行分析,在多个仿真场景中均优化了星上资源利用,缓解了拥塞问题,在最优参数场景下实现了0丢包,吞吐量有5%以上的提升。 展开更多
关键词 低轨卫星通信 确定性网络 流量调度 异步流量整形 星上交换 NS3
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基于三维copula函数的多水文区丰枯遭遇分析 被引量:47
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作者 谢华 罗强 黄介生 《水科学进展》 EI CAS CSCD 北大核心 2012年第2期186-193,共8页
不同水文区的丰枯遭遇概率分析属于多变量概率分布问题,涉及的水文区越多,变量的维数就越高,问题就越复杂.为找到一种简单通用的多变量(n≥3)水文概率问题的求解方法,以不同水文区丰枯遭遇概率分析为例,引入三维copula函数构建多变量联... 不同水文区的丰枯遭遇概率分析属于多变量概率分布问题,涉及的水文区越多,变量的维数就越高,问题就越复杂.为找到一种简单通用的多变量(n≥3)水文概率问题的求解方法,以不同水文区丰枯遭遇概率分析为例,引入三维copula函数构建多变量联合概率模型,将其用于分析长江、淮河及黄河流域的径流量的联合概率和条件概率问题。研究结果表明,当变量维数n≥3时,由copula函数可以很容易地构建多变量概率分布模型;对一组水文数据系列,有多个不同copula函数可以选择,可采用拟合优度检验方法择优;copula函数构建的多变量概率模型,可以计算各种条件下的联合概率分布,可以分析各种不同量级水文变量的遭遇概率和条件概率;通过与多维转换为一维方法的比较,三维Frank copula函数具有更优良的拟合优度、无偏性及有效性,且计算更简便。 展开更多
关键词 三维copula函数 丰枯遭遇 多变量 概率分布模型
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船舶驱动用异步电机三维温度场研究 被引量:13
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作者 丁树业 关天宇 崔广慧 《哈尔滨理工大学学报》 CAS 北大核心 2015年第5期1-7,共7页
为研究船舶驱动用异步电机传热性能及温升特性,以一台Y2-250M-4型、55 k W异步电机为例,采用有限体积元法对其三维稳态温度场求解计算,分析了电机额定负载运行时主要部位的温升特性.同时,根据其船舶驱动的用途特点,实际运行时负载多呈变... 为研究船舶驱动用异步电机传热性能及温升特性,以一台Y2-250M-4型、55 k W异步电机为例,采用有限体积元法对其三维稳态温度场求解计算,分析了电机额定负载运行时主要部位的温升特性.同时,根据其船舶驱动的用途特点,实际运行时负载多呈变化,因此对电机不同负载工况的温升进行求解并对比分析.通过搭建实验平台,将实验数据与计算结果相对比验证.结果表明:无论何种工况,电机的最高温升均出现在转子导条处;随着负载的增大,电机各主要部位的最高温升呈增加趋势,并且其增幅逐渐趋于显著.该研究为电机设计及性能优化、故障预测提供一定参考. 展开更多
关键词 异步电机 三维温度场 温升 不同负载工况
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双绕组异步发电机数学模型dq轴解耦问题研究 被引量:3
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作者 顾伟峰 马伟明 王东 《中小型电机》 北大核心 2004年第5期1-5,共5页
12/3相双绕组异步发电机是将交直流双绕组发电理论应用到异步发电中、作为独立电源而提出的。这种电机在定子上布置了两套绕组。本文给出了双绕组异步发电机的数学模型 ,详细地分析了这种电机在dq0坐标系下数学模型中不同三相绕组之间d... 12/3相双绕组异步发电机是将交直流双绕组发电理论应用到异步发电中、作为独立电源而提出的。这种电机在定子上布置了两套绕组。本文给出了双绕组异步发电机的数学模型 ,详细地分析了这种电机在dq0坐标系下数学模型中不同三相绕组之间dq轴不解耦的原因。通过分析得出为了简化分析可以忽略不同套三相绕组dq轴之间不解耦的互漏抗而使系统dq轴之间解耦的结论。 展开更多
关键词 三相绕组 双绕组异步发电机 12/3相双绕组 定子 解耦 交直流 漏抗 电源 数学模型 系统
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三相异步电动机试验系统软件设计 被引量:2
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作者 许海翔 吴峰崎 姚文庆 《起重运输机械》 2015年第11期101-106,共6页
在VB环境下,根据GB 1032—2008《三相异步电动机试验方法》开发系统软件设计,文中介绍了电机试验系统控制及数据分析软件的流程和具体实现方式。该系统具有自动化程度高、数据采集精度高等优点。
关键词 三相异步电动机 试验系统 软件
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三相异步电动机可靠性和经济分析 被引量:1
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作者 刘宝友 方攸同 徐兰栓 《中小型电机》 北大核心 2002年第1期42-45,共4页
根据三相异步电动机的主要失效模型,利用概率分析和补充变量方法,求得了三相异步电动机的可靠性指标和运行的经济指标。
关键词 三相异步电动机 可靠性 经济性 概率分析 经济指标
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网络无纸化考试系统研究与实现 被引量:3
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作者 胡双炎 易连结 《科学技术与工程》 2009年第23期7034-7039,共6页
介绍了网络无纸化考试系统的设计方案,阐述了系统的逻辑结构、开发环境、模块组成以及部分实现等。并且使用开发工具ASP.NET2.0、Ajax、SQLServer实现了本3层B/S系统。实践结果表明,本系统是一个通用的、具有高用户体验的、先进的、安... 介绍了网络无纸化考试系统的设计方案,阐述了系统的逻辑结构、开发环境、模块组成以及部分实现等。并且使用开发工具ASP.NET2.0、Ajax、SQLServer实现了本3层B/S系统。实践结果表明,本系统是一个通用的、具有高用户体验的、先进的、安全的考试系统。 展开更多
关键词 网络 无纸化考试系统 ASP.NET2.0 AJAX SQL SERVER 3层B/S
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三相异步电动机绕组引接线的选择 被引量:1
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作者 李利娟 张利兵 许文耀 《电机技术》 2013年第3期42-43,45,共3页
详细介绍三相异步电动机绕组引接线选择时需要考虑的因素,重点介绍截面积大小的确定。
关键词 三相异步电动机 引接线 截面积 相电流
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高校科研管理系统研究与实现 被引量:3
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作者 胡双炎 游新娥 《娄底职业技术学院学报(职教与经济研究)》 2010年第1期55-59,共5页
介绍了高校科研管理系统的设计方案,阐述了系统的逻辑结构、开发环境、模块组成以及部分关键技术等。并且使用开发工具ASP.NET2.0、Ajax、SQL Server实现了本3层B/S系统。实践结果表明,本系统是一个通用的、具有高用户体验的、先... 介绍了高校科研管理系统的设计方案,阐述了系统的逻辑结构、开发环境、模块组成以及部分关键技术等。并且使用开发工具ASP.NET2.0、Ajax、SQL Server实现了本3层B/S系统。实践结果表明,本系统是一个通用的、具有高用户体验的、先进的、安全的科研管理系统。 展开更多
关键词 高校科研管理系统 ASP.NET2.0 AJAX SQL SERVER 3层B/S系统
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